Acylaminohydroxydiphenyl coupler



Patented Apr. v4, 1944 UNITED "STATES. PATENT orrlcr i scrmMlNonrnnoxrmrnnnrr. Y. courmn,

Henry D. Porter, Arnold Weissberger, and Paul W. Vittum, Rochester, N. Y., assignors to Eastman Kodak Company, Rochester, N. Y., a corporation of New Jersey No Drawing. Application June 12, 1942, Serial No. 446,776

4 Claims. (Cl. 95-6) This invention relates to photographic color forming compounds and particularly to color forming coupler compounds comprising certain acylamino phenols. r

The formation of colored photographic images by coupling the development product of aromatic attached to it. The dyes produced by coupling are azomethines, indamines or indophenols depending upon the composition of the coupler and of the developer. I

The principal disadvantages which have been encountered in the use of dyes of this type are undesirable light transmission characteristics and instability of the dyes to heat and light. The most desirable dyes would be those which transmit two of the primary colors completely and absorb the third primary color completely. For example, the cyan or blue-green dye should absorb red light completely and transmit blue and green light completely. It should retain these transmission characteristics over a long period of time and should withstand reasonable exposures to heat and light without appreciable fading or loss of its light transmission characteristics. Many of the available couplers, however, have been found not to produce dyes having these valuable characteristics. a

It is, therefore, an object of the present invention to provide novel photographic coupler compounds producing dyes which have desirable properties with respect to heat and light stability.

A further object is to provide novel couplers caporated in a photographic emulsion layer by dissolving them in an alkaline solution and mixing the solution with the emulsion, or by dissolving them in a water-insoluble, water-permeable material and dispersing the. solution in a silver halide photographic emulsion having a watersoluble colloid, such as gelatin, as the carrier material.. The couplers which we propose to' use havethe following general structure:

X X IIIHC 0-R a i where one X represents a hydroxyl group and the other Xs represent hydrogen atoms and R is an aryl or aryloxy alkyl radical, or an alkyl group having a carbon chain of at least eleven carbon atoms.

More specifically the compounds which we prefer to use have the following structure:

where R, as in the formula above, represents an aryl group, an aryloxy alkyl group or an alkyl group having a carbon chain of at least eleven carbon atoms. Where R. is an aryl or aryloxyallwl group, it need not contain a chain of at least eleven carbon atoms. In. both of these formulas, other substituents may or may not be present in either nucleus; for example, alkyl or halogen, but there should be no hydroxyl substituent in the nucleus containing the acetamide pable of producing blue-green dye images in photographio emulsion layers. A still further object is to provide novel couplers which may be incorporated in photographic emulsion layers.

These objects are accomplished, according to our invention, by the use as coupler compounds of certain acylaminohydroxydiphenyls in which the acylamino group is in the ring not containing the hydroxyl group. i

The couplers of our invention may be incorradical.

A further requirement considered necessary with these couplers, as with all couplers of the phenol class which react with the development product of aromatic amino developers, is that the ortho position or the para position with respect to the phenolic hydroxyl group be unsubstituted or substituted with a readily replaceable group. Where halogen substituents are present in the phenol nucleus, as indicated above, such substituents may be present even in the para position with respect to the phenolic hydroxyl group since these roups are readily replaceable in the coupling reaction. It is, desirable, therefore, that the position para to the phenolic hydroxyl group be unoccupied by an irreplaceable group.

The following compounds illustrate the gention:

eral class which we have found suitable for use as couplers:

(l) OH NH-C O-cn-oO-mm 2-hydroxy-4-[a-(p-tert.butylphenoxy)-propionamido]-diphenyl sulfosuccinic acid in 60 cc. of water by passing the mixture several times through a. colloi mill. Th methyl propionate and part of the water are evaporated from the emulsion by heating on a steam bath, while stirring, leaving a fine dispersion of the solution of the coupler in n-amyl sebacate. This dispersion is added to 100 cc. of a gelation silver halide emulsion and coated in the usual manner. After exposure, this emulsion may be developed in the following solution:

04311-00643 2-amino-5-diethylaminotoluene HC1 grams 2 1 km Sodium sulfite do 2 Sodium carbonate do 2-hydroxy-4-chloro-f-[a-(p-tert.butylphenoxy)-propionamido]- Potassium bromide d0 2 0 Water to liter 1 HOUUNH- O t-hydrory-ZV-{m-(p-iertamylphenoxy) benzamidel-diphenyl 2-hydroxy-4-chloro-4-(palmityl-amino)-diplienyl These couplers are prepared by replacement of one 01 the hydrogen atoms of the amine group of the aminohydroxydiphenyl (U. S. P. 2,001,523) group by an acyl group in the following manner: By the action of the appropriate acid chloride in acetic acid solution with sodium acetate as the condensing agent. Other solvents and condensing agents such'as pyridine may also be used.

As indicated above, our couplers may be incorporated directly in photographic emulsion layers from alkaline solution or may be dissolved in a water-insoluble, water-permeable solvent and dispersed in the emulsion layer. Water-insoluble. water-permeable solvents for the couplers include materials such as cellulose esters, natural and synthetic resins and high boiling crystalloidal materials such as triphenyl phosphate. Methods for the incorporation of couplers in this way are described in Martinez U. 8. Patent 2,269,158,

granted January 6, 1942, Mannes and Godowsky U. S. Patent 2,304,940, granted December 15, 1942, and Jelley and Vittum U. S. Patent 2,322,027, granted June 15, 1943.

The following examples illustrate our inven- Ezample 1 After development, the emulsion may be fixed in the usual acid-alum fixing bath, washed and the silver removed by successive treatments in ierricyanide bromide solutions and hypo.

Example 2 The direct incorporation of a coupler in an emulsion is illustrated by the following example:

A solution is prepared containing 1 gram of 2- hydroxy- 4 -chloro-4- (palmitylamino) -diphenyl, 13 cc. 0! ethyl alcohol and 1 cc. of 2.0% sodium hydroxide solution. This solution is mixed with cc. of a melted red-sensitized gelatino silver bromide emulsion and to the resulting mixture is 35 added enough 10% citric acid solution to bring the pH of the emulsion back to its original value. This emulsion is then coated in the normal manner and may be processed as described in Example 1. The couplers of our invention yield dyes having better light absorption characteristics and iastness to light and heat than dyes from previously known couplers suitable for addition to emulsion layers to produce cyan dyes.

..-While we have referred to the incorporation of our couplers in silver halide emulsion layers, it will be understood that the couplers may also be incorporated in the developing solutions themselves. In the latter method, the couplers must be so constituted with regard to molecular size and solubility that they are soluble in the de- 'veloper and capable of diffusion through gelatin. In the case of couplers having a simple aliphatic acid acyl group attached to the amino nitrogen atom, for example, those having an alkyl group with a carbon chain of less than eleven carbon atoms will, in general, be suitable for incorporation in photographic developing solutions.

In the development of exposed silver halide emulsion layers using the couplers oi our invention, any color-forming developer containing a primary amino group may be used. These include developers having two primary amino roups as well as those having one of the amino groups substituted or having substituents in the ring such as alkyl phenylene diamines. These compounds are usually employed in the salt form such as the hydrochloride or the sulfate which are more stable than the amines themselves. Suitable compounds are diethyl-p-phenylenediamine hydrochloride, monomethyi-p-phenylenediamine hydrochloride, dimethyl-p-phenylene diamine hydrochloride and Z-amino-S-diethylaminotoluene hydrochloride. "The p-aminophenols and their substitution products may also be used where the amino group is unsubstituted. All ot'these coated as a single layer on the support or as superposed layers on one or both sides or the support. Thesuperposed layers may be differentially sensitized and the dyes formed therein by coupling may be bleached by an oxidizing agent such as .chromic acid to colorless soluble compounds. The destruction of the dye in'this way does not destroy the silver image and the silver image may be developed, bleached and developed to color images in superposed layers as described, for example, in Mannes and Godowsky U. S. Patent No. 2,113,329. Since the couplers of our irrvention produce cyan dyes, they will usually be incorporated in the red-sensitive emulsion layer of a multi-layer coating although they may be incorporated in layers otherwise sensitized when false colors are to be produced.

The examples and compounds set forth in the present specification are illustrative only and it is to be understood that our invention is to-be taken as limited only by the scope of the appended claims.

We claim:

l. A gelatino-silver halide emulsion for color photography containing a substantially nondiffusing color-forming compound having the following structural formula:

X X IIIHCO-R insoluble, water-permeable material having dissolved therein a color-forming compound having the following structural formula:

- x x IIIHC O-R where one X is a hydroxyl group and the other Xs are hydrogen atoms, and R is a group selected from the class consisting of aryl and aryloxy alkyl groups, and alkyl groups having a carbon chain of at least 11 carbon atoms, the nucleus containing the acetamide group being free of hydroxyl groups.

3. A color-forming photographic emulsion comprising a gelatino-silver halide layer containing dispersed particles of a water-insoluble waterpermeable material having dissolved therein a color-forming compound having the following structural formula:

x .x ITIHCO-R ll x x developing agent in the presence or a coupler compound having the structural formula:

' x x 1 -IHo0- R 

